Re: [PATCH 1/4] vdpa/mlx5: Fix rule forwarding VLAN to TIR

From: Michael S. Tsirkin
Date: Wed Oct 19 2022 - 01:39:35 EST


On Wed, Oct 19, 2022 at 05:36:17AM +0000, Eli Cohen wrote:
> > From: Michael S. Tsirkin <mst@xxxxxxxxxx>
> > Sent: Wednesday, 19 October 2022 8:34
> > To: Eli Cohen <elic@xxxxxxxxxx>
> > Cc: Si-Wei Liu <si-wei.liu@xxxxxxxxxx>; jasowang@xxxxxxxxxx; linux-
> > kernel@xxxxxxxxxxxxxxx; virtualization@xxxxxxxxxxxxxxxxxxxxxxxxxx;
> > eperezma@xxxxxxxxxx; lulu@xxxxxxxxxx
> > Subject: Re: [PATCH 1/4] vdpa/mlx5: Fix rule forwarding VLAN to TIR
> >
> > On Wed, Oct 19, 2022 at 05:31:48AM +0000, Eli Cohen wrote:
> > > > From: Si-Wei Liu <si-wei.liu@xxxxxxxxxx>
> > > > Sent: Tuesday, 18 October 2022 22:21
> > > > To: Eli Cohen <elic@xxxxxxxxxx>; mst@xxxxxxxxxx; jasowang@xxxxxxxxxx;
> > > > linux-kernel@xxxxxxxxxxxxxxx; virtualization@xxxxxxxxxxxxxxxxxxxxxxxxxx
> > > > Cc: eperezma@xxxxxxxxxx; lulu@xxxxxxxxxx
> > > > Subject: Re: [PATCH 1/4] vdpa/mlx5: Fix rule forwarding VLAN to TIR
> > > >
> > > > Hi Eli,
> > > >
> > > > It's not for this patch but something related, so just a friendly
> > > > heads-up. I haven't validated the VLAN tagging behavior yet for mlx5
> > > > vdpa, but from my quick read of the code it doesn't seem it
> > > > differentiates the case with and without VIRTIO_NET_F_CTRL_VLAN, to be
> > > > compatible/compliant with what's been implemented in QEMU software (a
> > > > spec addendum was filed as requested by Michael):
> > > >
> > > > https://github.com/oasis-tcs/virtio-spec/issues/147
> > > >
> > > > - when VIRTIO_NET_F_CTRL_VLAN is negotiated, the device starts with
> > > > all VLANs filtered (meaning only untagged traffic can be received,
> > > > and traffic with VLAN tag will be dropped).
> > > >
> > > > - when VIRTIO_NET_F_CTRL_VLAN is not negotiated, all traffic including
> > > > untagged and tagged can be received.
> > > >
> > > > Can you please help check if we need further fix in terms of VLAN tagging?
> > > >
> > >
> > > Sure. It's broken today. I will fix this to conform to the above requirements
> > and send V1.
> >
> > Did you mean v2?
> >
>
> I count from 0 and have been following this scheme but I can make it v2 if that's the norm.

Yes, most people seem to count patches from 1 so [PATCH] is followed by
[PATCH v2]. I don't know why. But it doesn't matter much - I just
wanted to understand whether you will be sending a new version of this
patchset. I know now.


> > > > Thanks,
> > > > -Siwei
> > > >
> > > >
> > > > On 10/18/2022 4:12 AM, Eli Cohen wrote:
> > > > > Set the VLAN id to the header values field instead of overwriting the
> > > > > headers criteria field.
> > > > >
> > > > > Before this fix, VLAN filtering would not really work and tagged packets
> > > > > would be forwarded unfiltered to the TIR.
> > > > >
> > > > > Fixes: baf2ad3f6a98 ("vdpa/mlx5: Add RX MAC VLAN filter support")
> > > > >
> > > > > Signed-off-by: Eli Cohen <elic@xxxxxxxxxx>
> > > > Reviewed-by: Si-Wei Liu <si-wei.liu@xxxxxxxxxx>
> > > >
> > > > > ---
> > > > > drivers/vdpa/mlx5/net/mlx5_vnet.c | 2 +-
> > > > > 1 file changed, 1 insertion(+), 1 deletion(-)
> > > > >
> > > > > diff --git a/drivers/vdpa/mlx5/net/mlx5_vnet.c
> > > > b/drivers/vdpa/mlx5/net/mlx5_vnet.c
> > > > > index 90913365def4..dd29fdfc24ed 100644
> > > > > --- a/drivers/vdpa/mlx5/net/mlx5_vnet.c
> > > > > +++ b/drivers/vdpa/mlx5/net/mlx5_vnet.c
> > > > > @@ -1472,7 +1472,7 @@ static int
> > mlx5_vdpa_add_mac_vlan_rules(struct
> > > > mlx5_vdpa_net *ndev, u8 *mac,
> > > > > if (tagged) {
> > > > > MLX5_SET(fte_match_set_lyr_2_4, headers_v, cvlan_tag, 1);
> > > > > MLX5_SET_TO_ONES(fte_match_set_lyr_2_4, headers_c,
> > > > first_vid);
> > > > > - MLX5_SET(fte_match_set_lyr_2_4, headers_c, first_vid, vid);
> > > > > + MLX5_SET(fte_match_set_lyr_2_4, headers_v, first_vid, vid);
> > > > > }
> > > > > flow_act.action = MLX5_FLOW_CONTEXT_ACTION_FWD_DEST;
> > > > > dest.type = MLX5_FLOW_DESTINATION_TYPE_TIR;
> > >
>